1. Field of the Invention
The present invention relates to a thin display module to be used as a display of a digital device, and more particularly, to a display module which is modularized integrally with an external circuit.
2. Description of the Related Art
In recent years, various digital devices are equipped with a thin display module which serves as a display. In particular, when the display module is employed for use in a device such as a mobile device which is carried outside, the display screen of the mobile device is required to have high visibility under ambient light. In order to improve the visibility of the display screen of the mobile device, it is necessary to suppress ambient light reflection.
As a method involving suppressing ambient light reflection, Japanese Patent Application Laid-Open No. 2003-173868 proposes to fill a gap between a display panel (device substrate) and a protective plate with oil having an appropriate refractive index, to thereby prevent degradation in visibility due to interface reflection to be caused between the display panel and the protective plate. Alternatively, Japanese Patent Application Laid-Open No. 2003-29644 proposes to intimately adhere the display panel and the protective plate to each other across one or more layers of a transparent adhesive material.
Further, a display module which includes a mounting component, such as an external IC (integrated circuit), mounted on a display panel has come into widespread use. In such a display module, the mounting component needs to be covered with a protective film after being mounted, to thereby protect the mounting component.
FIG. 4 is a schematic cross-sectional view illustrating an example of a configuration of a display module. FIG. 4 illustrates a polarizing plate 21, a protective plate 22, a filler 23, a sealing member 24, a mounting component (external IC) 25, a display panel 26, a casing 27, a circuit protective resin 28, and a FPC (flexible printed circuit) 29.
In the display module illustrated in FIG. 4, the filler 23 is filled between the display panel 26 and the protective plate 22 for the purpose of suppressing ambient light reflection occurring at an interface between the display region of the display panel 26 and the protective plate 22. Further, for protection of the mounting component 25 such as an external IC, the protective resin 28 separately covers the mounting component 25, to thereby protect the mounting component 25.
Meanwhile, in the conventional display module, the filler 23 is filled in a gap forming the interface between the display region of the display panel 26 and the protective plate 22 for the purpose of preventing ambient light reflection, while the protective resin 28 is separately employed to cover the mounting component 25 for protection. Accordingly, the films in the display region of the display panel 26 and in the mounting component 25 are formed of different materials in different processes, which leads to a problem that the number of production steps increases. Further, the mounting component 25 is not disposed in proximity to the effective display region, which leads to another problem that the display panel is increased in size and thickness, resulting in an increase in cost of production.